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(function() {
Set = function() {
this.elems = {};
};
_.extend(Set.prototype, {
add: function(obj) {
var hash = this._getHash(obj);
if(this.elems[hash] == undefined) {
this.elems[hash] = obj;
}
},
remove: function(obj) {
var hash = this._getHash(obj);
if(this.elems[hash]) {
delete this.elems[hash];
}
},
member: function(obj) {
var hash = this._getHash(obj);
return !!this.elems[hash];
},
contains: function(obj) {
return this.member(obj);
},
size: function () {
return _.size(this.elems);
},
isEmpty: function() {
return this.size() == 0;
},
each: function(k, cxt) {
_.each(this.elems, k, cxt);
},
_getHash: function(obj) {
var str = obj.toString();
// the same hash function that java uses for String.hashCode
return _.reduce(str, function(hash, c) {
hash = ((hash << 5) - hash) + c.charCodeAt();
return hash & hash;
}, 0);
}
});
})();
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